/*
 * Copyright (C) 2011 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.primitives;

import com.google.common.annotations.GwtCompatible;

/**
 * A string to be parsed as a number and the radix to interpret it in.
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class ParseRequest
{
    final String rawValue;
    final int radix;

    private ParseRequest(String rawValue, int radix)
    {
        this.rawValue = rawValue;
        this.radix = radix;
    }

    static ParseRequest fromString(String stringValue)
    {
        if (stringValue.length() == 0)
        {
            throw new NumberFormatException("empty string");
        }

        // Handle radix specifier if present
        String rawValue;
        int radix;
        char firstChar = stringValue.charAt(0);
        if (stringValue.startsWith("0x") || stringValue.startsWith("0X"))
        {
            rawValue = stringValue.substring(2);
            radix = 16;
        }
        else if (firstChar == '#')
        {
            rawValue = stringValue.substring(1);
            radix = 16;
        }
        else if (firstChar == '0' && stringValue.length() > 1)
        {
            rawValue = stringValue.substring(1);
            radix = 8;
        }
        else
        {
            rawValue = stringValue;
            radix = 10;
        }

        return new ParseRequest(rawValue, radix);
    }
}
